Structure of a semiconductor array

ABSTRACT

A structure of a semiconductor array comprises multiple a backplane driver, wherein the backplane driver having a first surface and a second surface; a plurality of compound semiconductor light emitting unit disposed in an array on the first surface of the backplane driver having a gap between any two adjacent ones, wherein the each compound semiconductor light emitting unit having a first surface and a second surface, wherein the second surface of the each compound semiconductor light emitting unit having a cathode and an anode, wherein the cathode and the anode of the each compound semiconductor light emitting unit electrically connected to the first surface of the backplane driver, and wherein the cathode and the anode of the each compound semiconductor light emitting unit are separated from each other from the adjacent electrodes of the adjacent compound semiconductor light emitting units; and a polymer layer disposed above the first surface of the each compound semiconductor light emitting unit.

This application claims benefit of U.S. patent application Ser. No.14/720,316 filed on May 22, 2015, U.S. provisional applications No.62/002,851 filed on May 24, 2015, No. 62/009,250 filed on Jun. 8, 2015and No. 62/009,251 filed on Jun. 8, 2015 under 35 U.S.C. § 119(e); theentire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates a structure of a semiconductor array, and moreparticularly to a structure of filling with a polymer in a streetbetween semiconductor units.

Related Art

There are many known semiconductor substrate removal technologies. Thesetechnologies include mechanical grinding removal, planer removal,chemical wet etching removal and laser irradiation the interfacial layerfor removal. For removal of semiconductor chip array from their growthsubstrate to another carrier, the protection structure of thesemiconductor chip array is a key to obtain high yield carrier transfer.More specifically, for the thin flexible display, there are many knowndisplay technologies such as the organic light emitting diode display,micro LED display. Recently, small size displays with high resolutionfor wearable electronic devices are getting more popular. Currently,most of small size high resolution display is fabricated by organiclight emitting diode. The organic light emitting diode display ispotentially used in many wearable electronic display, head mounteddisplay, smart watch display, smart band display, and smart ringdisplay.

SUMMARY OF THE INVENTION

The invention discloses a structure of a semiconductor array comprisesmultiple semiconductor units, an isolation layer and a decomposed orbuffer unit. Multiple semiconductor units combined the semiconductorarray. The isolation layer coated each semiconductor unit. Thedecomposed or buffer unit coated the isolation layer and filled betweeneach semiconductor unit to enhance structure of the semiconductor units.Wherein, the isolation layer protected by edge of the semiconductorunits and the decomposed or buffer unit.

In one embodiment of the present invention, the isolation layer and thepolymer are provided to separate each single semiconductor lightemitting unit. Two neighbor semiconductor light emitting unit structurecould be separated by the isolation layer and the polymer. The lightemitted from each semiconductor light emitting unit could be confined bysaid polymer. Each semiconductor light emitting unit could onlypropagate within a single semiconductor light emitting unit region. Thepolymer provides continuous structure to connect the matrix array of thesemiconductor light emitting units. In another embodiment of the presentinvention, a color conversion layer is formed on top of each singlesemiconductor light emitting unit to convert the light from a firstspectrum to a second spectrum.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention.

FIG. 1 is a schematic cross section diagram of a semiconductor chiparray on a substrate, and an isolation layer on the edge of eachsemiconductor unit.

FIG. 2 is a schematic cross section diagram of a semiconductor chiparray and edge surrounding isolation layer mounting to a carrier.

FIG. 3 is a schematic cross section diagram of filling with the polymerin a street between semiconductor chip array units and the carrier.

FIG. 4 is a schematic cross section diagram of covering with the polymerlayer in a street between semiconductor chip array units and the carrierand forming an air gap.

FIG. 5 is a schematic cross section diagram of FIG. 3 structure afterremoving the substrate.

FIG. 6 is a schematic cross section diagram of FIG. 4 structure afterremoving the substrate.

FIG. 7 is a schematic cross section diagram of multiple semiconductorlight emitting array units filling with the polymer mounting on thebackplane (driver).

FIG. 8 is the top view of the FIG. 7, showing an example of 4×4semiconductor light emitting array units filling with the polymermounting on the backplane (driver).

FIG. 9 is a schematic cross section diagram of multiple semiconductorlight emitting array units covering with the polymer layer mounting onthe backplane (driver).

FIG. 10 is the top view of the FIG. 9, showing an example of 4×4semiconductor light emitting array units covering with the polymermounting on the backplane (driver).

FIG. 11 is a schematic cross section diagram of FIG. 7 structure afterremoving the substrate.

FIG. 12 is a schematic cross section diagram of FIG. 9 structure afterremoving the substrate.

FIG. 13 is the separated semiconductor light emitting array units on thebackplane (driver) after removing the substrate and polymer.

FIG. 14 is a scheme cross section diagram, showing a conformalinsulation layer could be coated on the FIG. 13 structure.

FIG. 15 is a schematic cross section diagram, showing an insulationpolymer layer could be coated on the FIG. 13 structure.

FIG. 16A is a schematic cross section diagram of a dam array patterningon top of the FIG. 12 structure.

FIG. 16B is a schematic view showing a three dimensional view of FIG.16A.

FIG. 17 is a schematic cross section diagram of color conversion layerpatterning on the structure of FIG. 16 in accordance with UV emittedsemiconductor light emitting array unit.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be apparent from the following detaileddescription, which proceeds with reference to the accompanying drawings,wherein the same references relate to the same elements.

FIG. 1 shows the scheme cross section diagram of a semiconductor array100 on a substrate 10, and an isolation layer 101 on the edge of eachsemiconductor unit 11. Multiple semiconductor units 11 combined thesemiconductor array 100. The semiconductor unit 11 and a street 12 couldbe defined by photolithography and patterning. The isolation layer 101could be deposited and patterning to form on the edge of thesemiconductor unit 11. In option, the isolation layer 101 could bepatterned proportion on top of the semiconductor unit 11. The isolationlayer 101 could be deposited by dielectric material such as SiO_(x),Si_(x)N_(y), Al₂O₃, TiO₂ using plasma enhance chemical vapor deposition,chemical vapor deposition, physical vapor deposition, atomic layerdeposition. The isolation layer 101 could be polymer such as polyimide,silicone, and epoxy.

FIG. 2 shows the scheme cross section diagram of semiconductor array 100and edge surrounding isolation layer 101 mounting to a carrier 20. Thecarrier 20 could be hard material such as Si wafer, glass, sapphire, orany semiconductor wafers. The carrier 20 could be flexible material suchas polyimide, plastics, thin glass or any material having flexible andsoft properties. The mounting process could be selected form solderbonding, glue attach, stamping. A street 12 could be formed between thesemiconductor unit 11 and the carrier 20.

In one embodiment, the invention provides a decomposed or buffer unit.The decomposed or buffer unit can be satisfied by a polymer. Pleaserefer to FIG. 3, FIG. 3 shows the scheme cross section diagram offilling with the polymer 30 in a street 12 between semiconductor units11 and the carrier 20. In another embodiment, FIG. 4 shows the schemecross section diagram of covering with the polymer 30 in a street 12between semiconductor units 11 and the carrier 20 and forming an air gap40. The polymer 30 could be single layer or multiple layers coveringinto the semiconductor array units.

The polymer 30 could be cured by thermal curing, UV curing, or IR curingafter photolithography patterning or filling. The polymer 30 could beselected from the hard materials, such as gels, glues, sol-gels, epoxy,silicone, polyimide, phenyl-silicone; photo-sensitive resister, UV cureable glues, and thermal cure able glues. The polymer 30 could be alsoselected from the stretch materials, such as gels, glues, epoxy,polyimide, parylene, silicone, methyl-silicone, cohesive gels, siliconegels, PMMA, photosensitive photoresist, UV or thermal cure able glues.

Now referring to FIG. 3, and FIG. 4, the polymer 30 formed in streetcould help to make the structure of the semiconductor units 11 morerobust. In one embodiment, one sandwich structure 31 could be formed bythe polymer 30, isolation layer 101 and the semiconductor units 11. Thesemiconductor unit 11 and the polymer 30 sandwich the isolation layer101. The isolation layer 101 could be supported well by the sandwichstructure. The isolation layer 101 could be protected by the edge of thesemiconductor units 11 and the polymer 30 which in the street 12. Inaddition, the continuous interfacial structure underneath of thesubstrate 10 could help to enhance the entire semiconductor array 100strength. For any additional further process steps, the continuousstructure could be sustained with no damage. For example, when applyinga physical force to remove the substrate 10, the polymer 30 couldprovide a continuous robust strength structure for the entiresemiconductor units 11 on the carrier 20 to prevent the damage/crack ofhard materials (or called brittle materials). The hard material (orcalled brittle material) could be the semiconductor chips layers, theisolation layer 101, and the cured polymer 30. In another embodiment,one sandwich structure 41 could be formed by air gap 40, the polymer 30,isolation layer 101 and the semiconductor units 11.

FIG. 5 shows the scheme cross section diagram of FIG. 3 structure afterremoving the substrate 10. FIG. 6 shows the scheme cross section diagramof FIG. 4 structure after removing the substrate 10.

The substrate 10 could be removed through different technologies. Theremoving of the substrate 10 could be performed through laserirradiation technology, substrate 10 grinding technology, chemical wetetching technology, planer, and mechanical substrate 10 removaltechnology. When substrate 10 is performed through laser irradiationtechnology, the semiconductor units 11 and polymer 30 are decomposedmaterials.

For the grinding, planer, and mechanical technologies, a violentphysical force to remove the substrate 10 is required. The continuousmaterials structure underneath of the interface of substrate 10 couldconnect and hold all of the materials together as a completelyconnecting structure. The isolation layer 101, polymer 30, and thesemiconductor unit 11 could be completely protected by the completelycompact connecting structure. The completely compact connectingstructure underneath of the substrate 10 could provide enough strengthto keep the whole structure more robust on the carrier 20 without damageduring the violent grinding process.

For the chemical wet etching technology, the substrate 10 may be removedor etched by violent chemical solution. The continuous materialsstructure underneath of the interface of substrate 10 could connect andhold all of the materials together as a completely connecting structure.The sandwich structure of the connecting materials could provide acompact continuous layer to stop the chemical solution penetration. Whenapplying the chemical solution to remove the substrate 10, thecontinuous compact interfacial structure underneath of the substrate 10could protect the entire structures on the carrier 20 without chemicaldamaging.

For the laser irradiation lift off, the laser could irradiate throughthe substrate 10 and interacting on the interface of the materialunderneath the substrate 10. The interfacial layers underneath of thesubstrate 10 could be decomposed or not decomposed. The continuousmaterials structure underneath of the interface of substrate 10 couldconnect and hold all the materials together as a completely compactconnecting structure. In other words, the polymer 30 is to fix a shapeof the semiconductor units 11 and buffer a stress of the semiconductorunits 11. The isolation layer 101, polymer 30, and the semiconductorunit 11 could be completely protected by the completely compactconnecting structure. The substrate 10 could be delaminated byadditional physical force from the completely compact connectingstructure. The connecting structure of isolation layer 101, polymer 30,and the semiconductor unit 11 could be no change before and afterapplying laser and another physical force to remove the substrate.

It should be noted that, the semiconductor units 11 and the polymer 30are decomposed materials when the removing of the substrate 10 isperformed through laser irradiation technology; the semiconductor units11 is decomposed materials when the removing of the substrate 10 isperformed through chemical wet etching technology.

For the particular case separation of substrate 10 by the laserirradiation, this method could be applied to any suitable process indifferent application filed such as semiconductor light emitting arrayunit display, touch panel, light emitting diode solid state lighting,micro engineering mechanical system, high power devices, solar cell,lithium battery, and other suitable semiconductor process. In anotherembodiment, such as flexible semiconductor light emitting array unitdisplay, flexible solar cell, flexible battery (flexible lithiumbattery), flexible light emitting diode solid state lighting, flexiblesensors, flexible panels, flexible electronics, the forming of thepolymer 30 in sandwich structures (31 or 41) and applying laserirradiation to transfer thin film devices to a flexible carrier could bevery useful methods to protect devices completely and save cost.

Now referring to FIG. 3, and FIG. 4, the substrate 10 could be replacedto any transparent material called “transparent substrate” for laserpassing through. The semiconductor unit 11 could be replaced to anymaterial having laser decomposition properties material called “firstlaser decompose able unit”. The isolation layer 101 could be replaced toany laser non-decomposition properties material called “lasernon-decompose able unit”, and the polymer 30 could be replaced to anylaser decomposition material called “second laser decompose able unit”.The laser passing through the “transparent substrate” and decomposingthe interfacial layer underneath of the “transparent substrate”. Thedecomposing interfacial layer is a portion the “first and second laserdecompose able unit”. After laser irradiation to these units underneathof the “transparent substrate 10”, the continuous materials structureunderneath of the “transparent substrate 10” could connect and hold allthe materials together as a completely connecting structure. The “firstlaser decompose able unit”, and “second laser decompose able unit”sandwich the “laser non-decompose able unit”. The completely compactconnecting structure could be robust to sustain any other physicalforce. The “transparent substrate 10” could be delaminated by additionalphysical force from the completely compact connecting structure. Pleasenote that the “laser non-decompose able unit” deposited on the“transparent substrate 10” could be peeled from the “transparentsubstrate 10” without damage due to well sandwich structure of the“first laser decompose able unit” and “second laser decompose ableunit”.

In some particular application such as the curved able or flexibleelectronic device application, the polymer 30 in the street 12 could beprovided as stretch properties to allow the bending force acting on theflexible devices without damaging. The stretch material could help tosupport the semiconductor units and provide flex properties to preventthe crack or damage of hard materials in the structure. For applicationof curved or flexible electronic devices, the stretch property ofpolymer 30 could provide a well supporting to maintain the integrity forthe structure of FIG. 5 and FIG. 6. During the bending action, thestretch polymer 30 could be extended well without separation.

FIG. 7 shows the scheme cross section diagram of multiple semiconductorunits 11 filling with the polymer 30 mounting on the driver. In theembodiment, each semiconductor units 11 is satisfied by a semiconductorlight emitting unit. The semiconductor units 11 includes n-type layer 11a, active layer 11 b, p-type layer 11 c, n-electrode 11 d, eutectic(solder) 11 e, cathode 11 f, p-electrode 11 g and anode 11 h. Singlesemiconductor light emitting unit is the direct bandgap compoundsemiconductor light emitting diode (LED). The LED epitaxy structuregrown on the substrate 10 consists of the initial growth epitaxy layer(n-type layer 11 a), the active layer 11 b, and the p-type layer 11 c.The semiconductor light emitting unit structure consists of thereflector layers, the isolation layer 101, the n-electrode layers, thep-electrode layers, and the eutectic (solder) layers. The electrodes ofsemiconductor light emitting unit is mounted to the cathode 11 f (forn-electrode 11 d), anode 11 h (for p-electrode 11 g) of the backplane(driver) by using eutectic (solder) 11 e. Between two neighborsemiconductor light emitting units, a street region is formed (isolated)as a street to separate each single semiconductor light emitting unit.Between the semiconductor light emitting unit and the backplane(driver), a region is formed as another street to isolate thep-electrode 11 g and n-electrode 11 f. The single semiconductor lightemitting unit could be provided as a light engine array unit of asub-pixel. The direct bandgap semiconductor light emitting unit hasself-emissive characteristics by current driving. Each sub-pixel lightengine unit could be controlled individually by the backplane (driver)to display images.

In the street region, as shown in FIG. 7, the polymer 30 is completefilling up to the edges of the single semiconductor light emitting unitand the backplane (driver). The polymer 30 fills up and covers on thebottom surface of the substrate 10 and covers on the top surface of thebackplane (driver). The isolation layer 101 (insulation layer) isforming on the edge of the each semiconductor light emitting unit. Thepolymer 30 fills up and covers the isolation layer 101. The polymer 30fills up and covers the sidewalls of electrodes (n-electrode 11 d andp-electrode 11 g) of each semiconductor light emitting unit. The polymer30 fills up and covers the sidewall of the eutectic (solder) 11 e layer,and the sidewall of the electrodes (cathode 11 f and anode 11 h) ofbackplane (driver).

The polymer 30 fill in the street region could be as a function of blackmatrix of array. The light emitted from each sub-pixel light enginearray unit could be confined to propagate the light only in each singlesub-pixel region. The light generated from each sub-pixel light enginearray unit could be irradiated to any angle and emitted to the neighborsub-pixels region. By filling polymer 30 in the street, the emittinglight of each sub-pixel light engine array unit could be absorbed (orsaid stopped) by street polymers. Thus, the polymer 30 formed in thestreet could be a function of black matrix array to prevent the lightcrosstalk effect. The polymer 30 underneath of the substrate 10 in thestreet region could connect all individual sub-pixel light engine arrayunits together. The continuous materials underneath of the substrate 10including the initial growth epitaxy layer, the isolation layer 101, thepolymer 30, could be connected together to form a robust continuousstructure.

In the region between cathode 11 f and anode 11 h within a singlesemiconductor light emitting unit, the region could be completely filledup polymer.

The semiconductor light emitting unit could be selected from differenttypes of chip structure such as flip chip type, or vertical type, orresonant cavity type light emitting diode (RCLED), or vertical cavitysurface emitted laser (VCSEL), or laser diode. The semiconductor lightemitting unit composites the epitaxy structure could be formed by directbandgap compound semiconductor light emitting diode. The emittingwavelength of semiconductor light emitting unit could be determined bythe energy bandgap of direct bandgap semiconductor. Different directenergy bandgap of the semiconductor light emitting material could beselected from III-V compound semiconductor such as In_(x)Ga_(1-x)N, GaN,Al_(x)Ga_(1-x)N, In_(x)Ga_(1-x)As, InGaP, GaAs, GaAsP, InP,(Al_(x)Ga_(1-x))_(y)In_(1-y)P, GaP.

The reflector underneath the p-type layer 11 c could be formed by highreflectivity metal layers such as Ni/Ag, Ni/Al, Ag alloyed, and Alalloyed metallization. In some particular purpose, the reflector layercould be formed by a semi-transparent contact such as Indium Tin Oxide(ITO) to make the contact to p-type layer 11 c and spread the current.After the semi-transparent contact forming, a distributed Braggreflector (DBR) layers could be deposited to reflect the high compactand directional light beam. For the high gamut of display requirement,the emitting light spectrum width of sub-pixel light engine could benarrowed by the DBR structure. The p-electrode 11 g and n-electrode 11 dcould be deposited underneath of the semiconductor light emitting unitby selecting metal layers. The electrode metal layers could be formed byselecting the metals from Ni, Cu, Al, Au, Ti, and its alloy. Thethickness of the electrodes metal layers could be greater than that ofthe thickness of one third epitaxy growth thickness. A eutectic metallayer or solder metal layers could be deposited underneath of theelectrodes of the semiconductor light emitting units. The eutectic(solder) 11 e layers as a connecting layers could be selected from AuSn,CuSn, Sn, CuAgSn, Indium, SnBi, or any suitable eutectic (soldering)metallization. In some particular case, the eutectic (soldering)metallization could be replaced to be an anisotropic conductive adhesivematerial could be forcefully connect the LED to the backplane (driver),the P-type and N-type can become fully insulated. For the anisotropicconductive adhesive material, it has metallic powder covering withnonconductive shield mixing in a polymer. The nonconductive shield couldbe broken by thermal bonding technology to provide anisotropicconductive function. For alignment purpose in this invention, the mixingpolymer should have semi-transparent properties. The backplane (driver)could be hard material such as glass, sapphire, Si wafer, or anysuitable semiconductor wafer. The backplane (driver) could be flexibleor stretchable material such as polyimide, plastic, thin glass. Thedata-lines and scan-lines of the backplane (driver) could be formed bypassive matrix (PM) driving mode or active matrix (AM) driving mode tocontrol the images display as commonly used display backplane (driver).The cathodes and anodes could be separated and patterned to form on topof the array circuit lines such as scan-lines and data-lines. Eachsub-pixel light engine array unit could be switched on and off byscanning to control the data-lines, and scan-lines circuit. Thedata-lines and scan-lines could be active mode driving mode andfabricated by Metal-Oxide-Semiconductor Field-Effect Transistor(MOSFET), Complementary Metal-Oxide-Semiconductor (CMOS), Thin-FilmTransistor (TFT), Low Temperature Poly-silicon (LTPS), Indium GalliumZinc Oxide (IGZO) methods to achieve.

By using IC technologies, a matrix of CMOS array module could be formedon the backplane (driver). Each CMOS array unit could be integratedcircuit design to connect with data line and scan line. Each sub-pixellight engine array turn-on or turn-off could be switched by each CMOSarray unit. By using a commonly used two transistors and one capacitycontrolling circuit to each CMOS array unit, each sub-pixel contrastratio, each sub-pixel brightness, each sub-pixel switch speed, eachsub-pixel gray level could be programmed, adjusted, tuning. Each CMOSarray unit could be controlled by image display control IC.

In another aspect, the backplane (driver) could be formed on anysuitable transparent hard carriers, such as sapphire, glass, quartz,acrylic, epoxy, PMMA etc., to provide a transparent carrier for someparticular application such as double side transparent display. In someparticular case, for the application of double side image display, thecircuit of the data-lines, scan-lines, electrodes could be formed bytransparent contact metallization or semitransparent contactmetallization such as ITO, IGZO, nano silver lines, or Graphene. Thematerial of the backplane (driver) could be selected from curve able,flexible, soft materials, such as polyimide, plastic, soft and thinglass, epoxy, PMMA, silicone, to provide a carrier for the curved andflexible display application.

For the flexible backplane (driver), in one embodiment, the commonlyactive matrix (AM) driving methods such as MOSFET, CMOS, TFT (Thin-FilmTransistor), LTPS (low temperature poly-silicon), and IGZO (indiumgallium zinc oxide) could be formed on the flexible material. In anotherembodiment, passive matrix driving methods such as stacking circuit withcathodes, and anodes could be formed by using 3D stacking circuit,flexible printed circuit film, Flexible Panel Circuit (FPC), Chip OnFilm (COF) fabrication technology on the flexible material.

The polymer 30 could be formed by patterning and filling. The polymer 30could be cured by thermal curing, UV curing, or IR curing afterphotolithography patterning or filling. The polymer 30 could be selectedfrom the hard materials, such as gels, glues, sol-gels, epoxy, silicone,polyimide, phenyl-silicone; photo-sensitive resister, UV cure ableglues, and thermal cure able glues. The polymer 30 could be alsoselected from the stretch materials, such as gels, glues, epoxy,polyimide, parylene, silicone, methyl-silicone, cohesive gels, siliconegels, PMMA, photosensitive photoresist, UV or thermal cure able glues.

In another aspect, the polymer 30 could be purposed as black matrixarray to absorb the light. The polymer 30 could be selected from dyeinghard materials, such as gels, glues, sol-gels, epoxy, silicone,polyimide, phenyl-silicone; photo-sensitive resister, UV cure ableglues, and thermal cure able glues. The polymer 30 could be alsoselected from dyeing stretch materials, such as gels, glues, epoxy,polyimide, parylene, silicone, methyl-silicone, cohesive gels, siliconegels, PMMA, photosensitive photoresister, UV or thermal cure able glues.The polymer 30 could be also purposed as black matrix to confine thelight within a sub-pixel region. The polymer 30 could be selected frommixing the polymer with sub-micro size powders. The powders could beselected from TiO₂, Al₂O₃, SiO₂, ZnO, Si. When the light hit the blackmatrix, the light could be refracted and reflected back to singlesub-pixel region by the sub-micro size powders mixing polymer.

Now referring to FIG. 8, the top view of FIG. 7 structure is shown inFIG. 8. FIG. 8 shows an example of the 4×4 matrix semiconductor lightemitting unit array. The region between two semiconductor light emittingarray units is called the street region. Each semiconductor lightemitting array unit could be separated by a street and the street couldbe occupied completely by polymer 30. From the top view of FIG. 7, FIG.8 illustrates each semiconductor light emitting unit has one interfacialepitaxy image (Called image 1) which is the initial interfacial growthepitaxy layer underneath of the substrate 10. In the 4×4 matrix array,an isolation layer 101 could be deposited surround on each semiconductorlight emitting unit has the second interfacial image (Called image 2)which is the isolation layer 101 underneath of the substrate 10. Theisolation layer 101 is surrounding covered on the edge of eachsemiconductor light emitting unit. In the street region, the polymer 30underneath of the substrate 10 shows another different interfacial image(Called image 3). The polymer 30 formed in the street region could helpto make the structure of the semiconductor light emitting units morerobust. One sandwich structure could be formed by the polymer 30 and thesemiconductor light emitting units. The semiconductor light emittingunit and the polymer 30 sandwich the isolation layer 101. The isolationlayer 101 could be supported well by the sandwich structure. Theisolation layer 101 could be protected by the edge of the semiconductorlight emitting units and the street polymer 30. In addition, thecontinuous interfacial structure underneath of the substrate 10 couldhelp to enhance the entire matrix array structure strength. For anyadditional further process steps, the continuous structure could besustained with no damage. For example, when applying a physical force toremove the substrate 10, the polymer 30 could provide a continuousrobust strength structure for the entire array sub-pixel light enginesto prevent the damage/crack of hard materials (or called brittlematerials). In other words, the polymer 30 is to fix a shape of thesemiconductor units 11 and buffer a stress of the semiconductor units11. The hard material (or called brittle material) could be the epistructure layer, the isolation layer 101, and the cured polymer 30.

In another embodiment for semiconductor light emitting unit displayapplication, FIG. 9 shows the scheme cross section diagram of multiplesemiconductor light emitting units covering with the polymer 30 layermounting on the backplane (driver). Similar as the structure of FIG. 7,each single semiconductor light emitting unit is the compoundsemiconductor light emitting diode (LED). The LED epitaxy structuregrown on the substrate 10 consists of the initial growth epitaxy layer(n-type layer 11 a), the active layer 11 b, and the p-type layer 11 c.The semiconductor light emitting unit structure consists of thereflector layer, the isolation layer 101, the n-electrode layer 11 d,the p-electrode layer 11 g, the eutectic (solder) 11 e layer. Theelectrodes of semiconductor light emitting units is mounted to thecathode 11 f (for n-electrode 11 d), anode 11 h (for p-electrode 11 g)of the backplane (driver) by using eutectic (solder) layer. Between twoneighbor semiconductor light emitting units, a street region is formed(isolated) as a street to separate each single semiconductor lightemitting unit. Between the semiconductor light emitting unit and thebackplane (driver), a region is formed as another street to isolate thep-electrode 11 g and n-electrode 11 d. The single semiconductor lightemitting unit could be provided as a single sub-pixel light engine unit.The direct bandgap semiconductor light emitting unit has self-emissivecharacteristics. Each sub-pixel light engine array unit could becontrolled individually by the backplane (driver) to display images.

In the street region, for the edge of each single semiconductor lightemitting unit, FIG. 9 shows the polymer 30 layer could cover the bottomsurface of the substrate 10, the single semiconductor light emittingunit sidewall edge and the top surface of the backplane (driver). Thepolymer 30 is a covering layer covers on the isolation layer 101surround on the sidewall edge of the single semiconductor light emittingunit. The polymer 30 is a covering layer covers on the sidewalls ofelectrodes (cathode 11 f and anode 11 h) of the single semiconductorlight emitting unit, the sidewall of the eutectic (solder) 11 e layer,and the sidewall of electrodes (cathode 11 f and anode 11 h) ofbackplane (driver). In the street region, the polymer 30 is only acovering layer and an Air gap 40 could be formed.

In another aspect, the covering polymer 30 in the street region could beas a function of black matrix of array. The light emitted from eachsub-pixel light engine array could be controlled to propagate in eachsingle sub-pixel region. The light generated from each sub-pixel lightengine array could be irradiated to any angle and emitted to theneighbor sub-pixels region. By covering the polymer 30 in the street,the emitting light of each sub-pixel light engine array could beabsorbed, stopped, or reflected by street polymers. Thus, the polymer 30formed in the street could be a black matrix array function to preventthe light crosstalk effect.

The polymer 30 underneath of the substrate 10 in the street region couldconnect all individual sub-pixel light engine array units together. Thecontinuous materials underneath of the substrate 10 including theinitial growth epitaxy layer, the isolation layer 101, the polymer 30,could be connected together to form a robust structure.

In the region between cathode and anode within a single semiconductorlight emitting unit, the polymer 30 could be only formed as a layerunderneath of the isolation layer 101 and on top of the backplane(driver). The polymer 30 is a covering layer covers on the sidewalls ofelectrodes (cathode, and anode) of the single semiconductor lightemitting unit, the sidewall of the eutectic (solder) layer, and thesidewall of electrodes (cathode 11 f and anode 11 h) of backplane(driver). Please note that the Air gap 40 could be formed in the regionbetween cathode 11 f and anode 11 h within a single semiconductor lightemitting unit.

Now referring to FIG. 10, the top view of the FIG. 9 structure is shownin FIG. 10. FIG. 10 shows an example of the 4×4 matrix semiconductorlight emitting unit array covering with the polymer 30 layer in thestreet. From the top view of FIG. 9, FIG. 10 illustrates eachsemiconductor light emitting unit has one interfacial epitaxy image(Called image 1) which is the initial interfacial growth epitaxy layerunderneath of the substrate 10. In the 4×4 matrix array, an isolationlayer 101 could be deposited surround on each semiconductor lightemitting unit has the second interfacial image (Called image 2) which isthe isolation layer 101 underneath of the substrate 10. The isolationlayer 101 is surrounding covered on the edge of each semiconductor lightemitting unit. The region between two semiconductor light emitting unitsis called the street region. In the edge region of the street,underneath of the substrate 10, the polymer 30 covering on the isolationlayer 101 has another interfacial image (Called image 3). In addition,in the middle of the street region, the image of the polymer 30 coveringon top surface of the backplane (driver) could be reflected through theair gap 40 and mixing with the polymer 30 covers on the bottom surfaceof substrate 10 in the middle of the street to show another image(Called image 4).

Now referring to FIG. 9, the covering polymer 30 layer formed in thestreet region could connect all the semiconductor light emitting unitstogether. The covering polymer 30 layer could help to make the structureof the semiconductor light emitting units more robust. In the streetregion and in the region between cathode and anode within a singlesemiconductor light emitting unit, the Air gap 40 was formed after thepolymer 30 covering. The Air gap 40 in the specific region could be afunction of air buffer to allow the structure of the semiconductor lightemitting units more flexible after substrate 10 removal.

The polymer 30 formed in the street region could help to make thestructure of the semiconductor light emitting units more robust. Onesandwich structure could be formed by the covering street polymer 30 andthe semiconductor light emitting units. The isolation layer 101 could besandwiched by the covering street polymer layer and the semiconductorlight emitting unit. The isolation layer 101 could be supported well bythe sandwich structure. The isolation layer 101 could be protected bythe edge of the semiconductor light emitting units and the coveringstreet polymer layer. In addition, the continuous interfacial structureunderneath of the substrate 10 could help to enhance the entire matrixarray structure strength. For any additional further process steps, thecontinuous structure could be sustained with no damage. For example,when applying a physical force to remove the substrate 10, the polymercould provide a continuous robust strength structure for the entirearray sub-pixel light engines to prevent the damage/crack of hardmaterials (or called brittle materials). The hard material (or calledbrittle material) could be the epitaxy structure layer, the isolationlayer 101, and the cured polymer 30. In addition, the air gap 40 couldbe a buffer to provide a buffer room for the entire matrix arraystructure more flexible to sustain the additional physical force.

Now referring to FIG. 7, and FIG. 9, the epi growth substrate 10 couldbe removed through different technologies. The removing of the growthsubstrate 10 could be performed through laser irradiation technology,substrate 10 grinding technology, chemical lift-off technology, andmechanical substrate 10 removal technology. Polymer 30 is to fix a shapeof the semiconductor units 11 and buffer a stress of the semiconductorunits 11.

For the laser irradiation technology, as the laser irradiate through thesubstrate 10 and interacting on the interface of the material underneaththe substrate 10. The major portion of the interfacial materialsunderneath of the substrate 10 may be decomposed. In some particularcase, some interfacial material underneath of the substrate 10 may stickon the substrate 10 without decomposition. In another particular case,some interfacial material underneath of the substrate 10 could bedecomposed, but stick back to the substrate 10 after laser irradiation.Thus, after laser irradiation, the substrate 10 could be removed byapplying additional physical force. After laser irradiation, there mayremain some interfacial material still stick on the underneath of thesubstrate 10. For example, the image 1 interface layer could bedecomposed by laser to be a metallic residue and a gas. The metallicresidue could help the semiconductor light emitting unit still fixing onthe substrate. The metallic residue is not a strong fixing material andcould be peeled off by additional physical force. The image 2 interfacelayer could not be decomposed by laser and still well stick on thesubstrate. The image 3 and image 4 interface layer could be decomposedto carbon residue. The carbon residue could help the polymer stillfixing on the substrate. The carbon residue is not a strong fixingmaterial and could be peeled off by additional physical force. Thecontinuous materials structure underneath of the interface of substrate10 could connect and hold all the materials together as a completelycompact connecting structure. The isolation layer 101, polymer 30, andthe semiconductor light emitting unit could be completely protected bythe completely compact connecting structure. The substrate 10 could bedelaminated by applying additional physical force from the completelycompact connecting structure. The isolation layer 101, polymer 30, andthe semiconductor light emitting unit could be no change before andafter applying laser irradiation and another physical force. Themetallic residue and carbon residue could be then cleaned up by chemicalsolutions.

For the grinding substrate 10 technology, the grinding of substrate 10has violent physical force to remove the substrate 10. The continuousmaterials structure underneath of the interface of substrate 10 couldconnect and hold all of the materials together as a completelyconnecting structure. The isolation layer 101, polymer 30, and thesemiconductor light emitting unit could be completely protected by thecompletely compact connecting structure. The completely compactconnecting structure underneath of the substrate 10 could provide enoughstrength to keep the whole structure more robust without damage duringthe violent grinding process.

For the chemical lift-off technology, the substrate 10 may be removed byviolent chemical solution. The invented structure of FIG. 1, and FIG. 3could provide a strong chemical resistant material underneath of thesubstrate 10. The initial growth epi layer, isolation layer 101 and thepolymer 30 are continuous structure in the street region. When applyingthe chemical solution to remove the substrate 10, the continuous compactinterfacial structure underneath of the substrate 10 could protect theentire structures of the semiconductor light emitting unit withoutchemical damaging.

For the mechanical lift-off substrate 10, a temporary layer could beinitial grown on the substrate 10. The temporary layer is purposed toprovide a mechanical lift off interfacial layer. After connecting thesemiconductor light emitting unit to the backplane (driver), thesubstrate 10 could be removed by applying a strong physical force suchas rotating or pulling up substrate 10 to delaminate the temporarylayer. The continuous materials structure underneath of the interface ofsubstrate 10 could connect and hold all of the materials together as acompletely connecting structure. The isolation layer 101, polymer 30,and the semiconductor light emitting unit could be completely protectedby the completely compact connecting structure. The invented structureof FIG. 1, and FIG. 3 with completely connecting structure underneath ofthe substrate 10 could provide a well supporting to prevent anymechanical damage.

FIG. 11 shows the scheme cross section structure of FIG. 7 afterremoving the substrate 10. The semiconductor light emitting units on thebackplane (driver) could still perform three different images. The threedifferent images are the Initial growth epitaxy layer (image 1), theisolation layer 101 (image 2), and the polymer 30 (image 3). Please notethat the semiconductor light emitting units on backplane (driver) aftersubstrate 10 removal has the same height of materials meaning that theimage 1, image 2, and image 3 are at the same level. The same heightmaterials could simplify additional fabricating process such as formingthe color conversion layer on top of the semiconductor light emittingunit. The polymer 30 in the street region could be purposed as afunction of black matrix of array to absorb, stop or reflect the lightescaping from the edge of semiconductor light emitting unit and preventthe crosstalk effect. In some particular, the substrate 10 might notneed to be removed. For rigid type monochrome display application, thenon-transparent polymer 30 in the street region as a black matrix couldprevent the light crosstalk issue.

FIG. 12 shows the scheme cross section structure of FIG. 9 afterremoving of the substrate 10. The semiconductor light emitting arrayunits on backplane (driver) could still perform four different images.The four images are the Initial growth epitaxy layer (image 1), theisolation layer 101 (image 2), the polymer 30 in the edge region of thestreet covering the isolation layer 101 (image 3), the polymer 30covering on top surface of the backplane (driver) could be reflectedthrough the air gap 40 and mixing with the polymer 30 in the middle ofthe street (image 4). Please note that the semiconductor light emittingunits on backplane (driver) after substrate 10 removal has the sameheight of materials, image 1, image 2, image 3, and image 4. The sameheight materials could simplify additional fabricating process. Thepolymer 30 in the street region could be purposed as a function of blackmatrix of array to absorb, stop or reflect the light escaping from theedge of semiconductor light emitting array unit and prevent thecrosstalk effect. In some particular, the substrate 10 might not need tobe removed. For rigid type monochrome display application, thenon-transparent polymer 30 in the street region as a black matrix couldprevent the light crosstalk issue.

In some particular application such as the curved able or flexibledisplay application, the polymer 30 in the street could be provided asstretch properties to allow the bending force acting on the displaymatrix. In the structure of FIG. 11, and FIG. 12, the polymer 30 couldbe selected from the stretch materials, such as gels, glues, epoxy,polyimide, parylene, silicone, methyl-silicone, cohesive gels, siliconegels, PMMA, photosensitive resister, UV or thermal cure able glues. Thestretch material described above could help to support the semiconductorlight emitting array units and provide flex properties to prevent thecrack or damage of hard materials in the structure. The hard materialssuch as the epitaxy structure, the isolation layer 101 are very thin inthe structure. The semiconductor light emitting array unit as a pixellight engine unit with isolation layer 101 surrounding on the edge couldbe very hard and brittle materials. For application of curved orflexible display, the stretch property of polymer 30 could provide awell supporting to maintain the integrity for the structure of FIG. 11,and the structure of FIG. 12. For the curved and flexible display,additional physical force to bend the display is a fundamentalrequirement. The stretch polymer 30 could grip to clamp thesemiconductor light emitting units and provide a flex buffer room toallow the bending force working on the semiconductor light emittingarray units without damaging the structure. Please note that the size ofthe semiconductor light emitting unit are ranging from 0.5 μm to 1000μm, the stretch polymer 30 allow a wide angle of bending for curved orflexible display application. During the bending action, the stretchpolymer 30 could be extended well without separation.

In another embodiment, referring to FIG. 11, and FIG. 12, the streetpolymer 30 could be removed after removing the substrate 10. Afterremoving substrate 10, top of the semiconductor light emitting units andthe polymer 30 will form a flat plane P.

FIG. 13 shows the street polymer 30 is removed. Each semiconductor lightemitting array unit could be separated only by an air gap 40 in thestreet. In FIG. 13, three images could be obtained from the top view.The initial growth epitaxy (image 1), the isolation layer 101 (image 2),and the air gap (the backplane (driver) surface) (called image 5). Forthe low cost mono color display application, due to each semiconductorlight emitting array units has isolation layer 101 covering andprotecting, the mono color display module could be applied for someparticular application.

In another embodiment, referring to FIG. 13, the empty street region andthe top of the semiconductor light emitting array units could be formedan insulation layer as a passivation layer. The insulation layer couldbe a conformal layer selecting from depositing parylene, SiN_(x), SiO₂or other suitable passivation materials. FIG. 14 shows a conformalinsulation layer could be coated on the FIG. 13 structure. In FIG. 14,the street region still remains an air buffer structure after conformalinsulation layer coating. The FIG. 14 structure could be applied forflexible mono color display application.

In another embodiment, the passivation layer could be another polymer 30layer coating on top of the semiconductor light emitting array unit andfill in the street region. FIG. 15 shows a polymer 30 layer coated onthe FIG. 13 structure. The entire FIG. 15 structure could keep a flattop surface for further process steps. Please note that the thickness ofthe polymer 30 layer should be better selected to be less than 10 μm toprevent the waveguide effect the light emitted from the sub-pixel lightengine light guiding to the neighbor sub-pixel region. For the flexibledisplay application, the backplane (driver) is flexible and could beselected from polyimide, plastic, thin glass. The covering polymer 30 ofFIG. 15 structure could be selected from stretch material such as gels,glues, epoxy, polyimide, parylene, silicone, methyl-silicone, cohesivegels, silicone gels, PMMA, photosensitive photoresist, UV or thermalcure able glues.

For the application of full color display, the color conversion layerscould be patterning on top of the FIG. 11, FIG. 12, FIG. 13, FIG. 14,and FIG. 15 structure in each one semiconductor light emitting arrayunit. In one embodiment, a dam array could be first formed on top of thestreet region of FIG. 12 structure. FIG. 16 shows a dam array could bedirectly patterned on top surface of the flat street of FIG. 12structure. FIG. 16B is a schematic view showing a three dimensional viewof FIG. 16A. Multiple dams D set on the flat plane and top of thepolymer to combine a dam array. The dam array could be as a black matrixto distinguish the light from each semiconductor light emitting arrayunit. The dam array could be deposited on top flat surface to cover thepolymer 30, isolator, and a portion of n-type layer. Please note thatthe dam array could be only selected forming on top of the polymer 30within the street. The dam array could be patterned through black dyeingphotoresist, or could be patterned by metal deposition.

FIG. 17 shows a different color conversion (wavelength conversion)layers could be formed in the dam directly on top of the FIG. 16Astructure. Multiple color conversion layers C set on the flat plane Pand filled in the dam array to convert the light of semiconductor lightemitting units from the a first spectrum to a second spectrum. In thecase of UV semiconductor light emitting array units as a sub-pixel lightengine, a blue conversion layer could be proportion patterned inside thedam on top of the n-type layer of the UV semiconductor light emittingarray unit, a green conversion layer could be proportion patternedinside the dam on top of the n-type layer of the UV semiconductor lightemitting array unit, and a red conversion layer could be proportionpatterned inside the dam on top of the n-type layer of the UVsemiconductor light emitting array unit.

The color conversion layers could be formed by using selective colorconverting phosphors, selective color converting quantum dots, and othermaterials having the various color converting properties. The patterningof the color converters could be formed by mixing phosphors or QDs withphoto-sensitive polymer 30 for photolithography. The photo-sensitivepolymer 30 could be photo-sensitive silicone, photo-sensitive PMMA,photo-sensitive polyimide, photo-sensitive epoxy, photo-sensitive gels,gules. The patterning of the color conversion layers could be fabricatedby photolithography, micro screen printing, micro jetting, micro inkjetprinting, micro contacting printing, micro dispensing, nano-imprinting,self-assembly, or other lithographic and photolithographic technologies.

To convert the UV emission semiconductor light emitting array units forfull color application, the color conversion layers could be a colorphosphor. The color phosphor could be selected to be micro and sub-microsize mixing with polymer for better color uniformity. The color phosphorfor example could be selected from the material such as Ca₂PO₄Cl:Eu²⁺,RbBaPO⁴:Eu²⁺ (RBP) phosphor for blue color conversion. The colorphosphor for example could be selected from the material such as (Ca,Sr, Ba,)₂(Mg, Zn)Si₂O₇:Eu, (Ba,Sr)₂SiO₄:Eu²⁺ phosphor for green colorconversion. The color phosphor for example could be selected from thematerial such as Sr₂Si₅N₈, CaAlSiN₃:Eu phosphor for red colorconversion. To convert the BLUE emission semiconductor light emittingarray units for full color application, the wavelength conversion layercould be a color phosphor. The color phosphor could be selected to besub-micro size mixing with polymer for better color uniformity. Thecolor phosphor for example could be selected from the material such as(Sr, Ga, Ba)S:Eu, SrSiON:Eu phosphor for green color conversion. Thecolor phosphor for example could be selected from the material such as(SrCa)AlSiN₃:Eu, (Ca, Sr, Ba)S:Eu phosphor for red color conversion. Thered (R) phosphor, green (G) phosphor, blue (B) phosphor could beproportionally patterning and filling by using micro dropping, microdispensing, micro screen printing, direct self-assembly, microcontacting printing, micro inkjet printing, or other lithographic andphotolithographic technologies.

The color conversion layers could be selected from Blue, Green, and Redquantum dots (QDs). The color converter material could be formed by sizeselective quantum dots (QDs) in polylaurylmethacrylate (PLMA) orpolymethyl methacrylate (PMMA). For example, the QDs can be selectedfrom CdSe/ZnS. The CdSe/ZnS/CdSZnS QDs for green conversion layer, andCdSe/CdS/ZnS/CdSZnS for red color conversion layer. The fill in processcould be done by using micro dropping, micro dispensing, micro screenprinting, direct self-assembly, micro contacting printing, micro inkjetprinting, or other lithographic and photolithographic technologies.

The color conversion layers could be selected from mixing polymer, fullcolor spectrum phosphor, and color filter photoresist. The color filterphotoresist could be selected from red, green, and blue colors. When theUV or blue light hit the full color spectrum phosphor, the light couldbe converted to a full color spectrum. The full color spectrum lightwill be absorbed by the color filter photoresist. The full colorspectrum light will only emit the color of its color filter spectrum.For example of mixing red color filter photoresist, the full colorspectrum light after phosphor will only emit the red color.

In another embodiment, the semiconductor light emitting array unitscould be the blue light emitting emission spectrum as the sub-pixellight engine. The blue conversion layer in FIG. 17 could be replaced toa transparent material.

In some particular case, the structure of FIG. 17 could be fabricated byusing another embodiment, the dam array and the color conversion(wavelength conversion) layers could be first formed on anothertransparent material (not shown in here). The patterning colorwavelength conversion layers and the dam array could be formed on thetransparent material. The transparent material having patterning colorconversion layers and dam array could be then aligned and mounted ontothe semiconductor light emitting array unit to provide a full colordisplay.

Thus the disclosure describes the method, and structure for fabricatinga continuous array cross-sectional sandwich structure for semiconductorchip array transforming and examples for semiconductor light emittingarray unit for display application. While a number of exemplary aspectsand embodiments have been discussed above, those of skill in the artwill recognize certain modifications, permutations, additions andsubcombinations thereof. It is therefore intended that the followingappended claims and claims hereafter introduced are interpreted toinclude all such modifications, permutations, additions andsub-combinations as are within their true spirit and scope.

While the present invention has been described by way of examples and interms of preferred embodiments, it is to be understood that the presentinvention is not limited thereto. To the contrary, it is intended tocover various modifications. Therefore, the scope of the appended claimsshould be accorded the broadest interpretation so as to encompass allsuch modifications.

What is claimed is:
 1. A semiconductor array comprising: a backplanedriver, wherein the backplane driver having a first surface and a secondsurface; a plurality of compound semiconductor light emitting unitdisposed in an array on the first surface of the backplane driver havinga gap between any two adjacent ones, wherein the each compoundsemiconductor light emitting unit having a first surface and a secondsurface, wherein the second surface of the each compound semiconductorlight emitting unit having a cathode and an anode, wherein the cathodeand the anode of the each compound semiconductor light emitting unitelectrically connected to the first surface of the backplane driver, andwherein the cathode and the anode of the each compound semiconductorlight emitting unit are separated from each other from the adjacentelectrodes of the adjacent compound semiconductor light emitting units;and a polymer layer disposed above the first surface of the eachcompound semiconductor light emitting unit.
 2. The semiconductor arrayaccording to claim 1, wherein the polymer is selected from the groupconsisting of gels, sol-gels, epoxy, silicone, polyimide, parylene,cohesive gels, silicone gels, PMMA, photosensitive photoresist, UV cureable glues, thermal cure able glues and dyeing polymer.
 3. Thesemiconductor array according to claim 2, wherein the polymer is mixedwith powders including TiO₂, Al₂O₃, SiO₂, ZnO and Si.
 4. Thesemiconductor array according to claim 1, wherein a wavelengthconversion material is placed on top of the compound semiconductor lightemitting unit to convert an original color from the compoundsemiconductor light emitting unit to a target color.
 5. Thesemiconductor array according to claim 4, wherein the wavelengthconversion material is at least one of a phosphor or a quantum dots. 6.The semiconductor array according to claim 1, wherein a dam arrayaligned over the gap, wherein the dam array has openings located abovethe first surface of the each compound semiconductor light emittingunit, and wherein the each opening is aligned to the each compoundsemiconductor light emitting unit.
 7. The semiconductor array accordingto claim 6, wherein the dam array is filled with a wavelength conversionmaterial.
 8. The semiconductor array according to claim 7, wherein thewavelength conversion material is at least one of a phosphor or aquantum dots.